Most means of high speed transportation provide a means for restraining an occupant seated in the vehicle. This includes an automobile, airplane or boat. Because this type of restraining means is generally designed for use by an adult passenger when he or she is seated, such a restraining means is not always appropriate for a child passenger.
In order to overcome the above disadvantage, child passenger securing apparatuses have been used wherein a smaller, auxiliary child's seat is positioned on a seat of a vehicle and secured to the seat by the vehicle's passenger restraining means. The child passenger is then seated in his or her own seat and, by the use of a harness formed from straps or webbing, is restrained into the seat and thereby is protected in case of an accident.
Several types of known child's seats employ reels apparatus for winding up the harness to take up any slack present after the child has been seated, as to store a portion of the harness when not in use. In this type of seat, the reel may be mounted at the rear of the backrest portion of the seat body, the leading end of the restraining harness is unwound from the reel and is passed over the rear portion of the seat's body, over the child's shoulders and is thereafter locked to the seat.
Many such seats use inertia-type reels which are spring-biased to exert a constant "reeling-in" tension on the harness. Such reels are common components in automobile seat belt systems and have the advantage of automatically taking up excess harness slack after the belt is fastened. The reel freely allows the harness belt to be pulled out, and locks upon the sudden change in acceleration encountered in an accidental impact.
Use of spring-biased inertia reels in child's seats has some inherent disadvantages. The reel may enable a child to create slack in the harness after it is locked by allowing more harness to be drawn from the reel. Excessive tensioning of the biasing spring may cause the harness to reel in suddenly when unlocked, causing the locking buckel to strike the child. Another disadvantage in the tendency of such reels to jam, making use of the seat impossible.
Such harnesses are shown in U.S. Pat. Nos. 4,679,852 and 4,660,889. Each of these inventions have difficult to use adjusting mechanisms with locking cams and other complicated mechanisms for restraining the child. Such mechanisms are difficult to utilize when a precocious child is being fastened into the seat for safety.
U.S. Pat. No. 4,688,849 (Tsuge) typifies the inertia reel securing apparatus for a child's car seat, having the disadvantages enumerated above. The inertia reel system is relatively complicated compared to the instant invention.
U.S. Pat. No. 4,025,111 (Tanaka et al.) discloses a restraining and buckle securing system quite similar to that of Tsuge except that no reel is provided and the slack in the harness must be taken up by manually adjusting individual slide buckles.
It is also known to provide a child seat with a harness such as shown in U.S. Pat. Nos. 4,025,111 and 4,342,483. Such harnesses typically includes a pair of belts slidably mounted to the back of the seat which extend over the chest of the child, with the belts having bottom ends removably locked by means of a seat belt buckle and tongue combination secured to the front lower portion of the seat.
One advantage to the use of inertial type belt systems is that the belt is free to move unless the vehicle is in a stopping mode during which the inertial retractor spool stops all such movement. However, when the vehicle is in motion, the belt is freely movable and may allow the child to free himself or herself from the restraining means thereby being exposed to potential harm in case of an accident. A restraining means or web adjuster is shown in U.S. Pat. No. 3,872,550 which discloses a pivotally mounted cam for releasably holding a belt. Operation of the adjuster allows for proper tensioning of the harness. Also known is a harness assembly wherein the ends of the belts are slidably mounted to a split tongue and then secured to the seat frame. The split tongue is removably and lockingly received by a buckle mounted to the seat.
Another drawback to prior seats and restraining harnesses is the excess webbing present which increased the cost of the unit, making more probable the chance of tangled webbing. 0f course, with any child seat it may be necessary to extract the child rapidly, and tangled webbing may interfere with rapid egress.
Therefore, one object of the present invention is to provide an improved child safety seat wherein the adjusting means utilizes a minimum amount of webbing while yielding a maximum amount of adjustability. By eliminating excess webbing, another object is met whereby storage means for excess webbing can be eliminated.
It is an object of the invention to provide a child seat in which the user can easily and quickly seat the child but, in an emergency, can rapidly extract the child therefrom.
Another object of the invention is to meet the above objects at a low cost, minimizing the amount of webbing and hardware in the child seat and encouraging the use of plastic parts to make the child seat lightweight and easily transportable.
Another object of the invention is to utilize a mechanism allowing a user to retract or extend the restraining means with one hand while assisting the child with the other hand.
Numerous other advantages and features of the invention will become readily apparent from the following detailed description of a preferred embodiment of the invention, from the claims, and from the accompanying drawings in which like numerals are employed to designate like parts throughout.